2-Substituted isovaleric acid ester pesticides

ABSTRACT

Compounds of the formula   &lt;IMAGE&gt;   wherein R is alkenyl, aralkyl or alkyl; X is H, CN, thioamide, or alkynyl; and Y is phenoxyphenyl or phthalimido, are useful as pesticides.

This is a division of application Ser. No. 687,483, filed May 18, 1976,now U.S. Pat. No. 4,042,710.

This invention relates to certain new substituted isovalerates, theiruse as pesticides and to pesticidal compositions containing these newisovalerates.

SUMMARY OF THE INVENTION

The present invention is directed to 2-substituted isovalerates of theformula I ##STR2## wherein R represents an alkyl or alkenyl group or anoptionally substituted aralkyl group; X represents a hydrogen atom, or acyano, thioamide or alkynyl group; and Y represents a phthalimido orphenoxyphenyl group.

Preferred compounds are those 2-substituted isovalerates of formula Iwherein R represents an alkyl group of 1 to 16 carbon atoms, which maybe branched, such as an isopropyl, isobutyl or isoamyl group, or may bestraight chain, such as methyl, ethyl, n-propyl, n-butyl, n-hexyl,n-octyl or n-dodecyl group, an alkenyl group of up to 6 carbon atoms,such as allyl, butenyl or pentenyl, or a benzyl group optionallysubstituted by one or more halogen atoms of atomic number of 9 to 35,inclusive, such as chlorine or by alkyl of 1 to 6 carbon atoms, such asmethyl; X represents a hydrogen atom, a cyano group, a thioamide groupor alkynyl of 2 to 6 carbon atoms, such as ethynyl; and Y represents aphenoxyphenyl or phthalimido group, especially a 3-phenoxyphenyl group.

Preferred because of their pesticidal properties are those compounds offormula I wherein R represents a branched chain alkyl group of 1 to 16carbon atoms or an alkenyl group of 2 to 6 carbon atoms or a benzylgroup optionally substituted by one or more halogen atoms or alkylgroups and Y represents a phenoxyphenyl group.

A particularly preferred subclass comprises those compounds of formula Iwherein R represents a branched chain alkyl group of 1 to 6 carbonatoms, an optionally alkyl substituted-allyl group or a benzyl groupoptionally substituted by halogen, especially chlorine or by an alkylgroup of 1 to 6 carbon atoms, especially methyl.

In general the compounds of formula I which are preferred are thosewhere X represents a cyano group.

The 2-substituted isovalerates of the invention may be prepared by aprocess which comprises reacting a compound of formula: ##STR3## with acompound of formula: ##STR4## wherein one of the groups Z and Arepresents a halogen, suitably chlorine or bromine, atom and the otherrepresents a hydroxy group; the other substituents having the meaningsdefined in formula I above. The reaction is conveniently carried out inthe presence of a hydrogen halide acceptor, suitably a carbonate such aspotassium carbonate, or a tertiary amine such as triethylamine, and inan organic solvent, such as toluene or acetone.

The compound of formula II may be prepared by appropriate adaptation ofknown synthesis procedures. Convenient routes include the reaction of a2-propyl halide (e.g. bromide) with a malonate or cyanoacetate, followedby reaction with the halide R--Hal and decarboxylation.

The isovalerates of the invention are of interest as pesticides,particularly as tickicides, insecticides and acaricides for agriculturaland domestic outlets. The invention therefore includes within its scopepesticidal compositions comprising a carrier and/or a surface-activeagent together with, as active ingredient, an isovalerate of formula I.Likewise the invention also includes a method of combating tick, insectand/or acarid pests at a locus which comprises applying to the locus apesticidally effective amount of an isovalerate derivative orcomposition of the invention. The compounds also have relatively lowtoxicities to fish and mammals.

The term `carrier` as used herein means a solid or fluid material, whichmay be inorganic or organic and of synthetic or natural origin, withwhich the active compound is mixed or formulated to facilitate itsapplication to the plant, seed, soil or other object to be treated, orits storage, transport or handling. The carrier may be a solid or afluid. Any of the materials usually applied in formulating pesticidesmay be used as the carrier.

Suitable solid carriers are natural and synthetic clays and silicates,for example natural silicas such as diatomacious earths; magnesiumsilicates, for example, talcs; magnesium aluminium silicates, forexample, attapulgites and vermiculites; aluminium silicates, forexample, kaolinites, montmorillinites and micas; calcium carbonates;calcium sulphate; synthetic hydrated silicon oxides and syntheticcalcium or aluminium silicates; elements such as for example, carbon andsulphur; natural and synthetic resins such as, for example coumaroneresins, polyvinyl chloride and styrene polymers and copolymers; solidpolychlorophenols; bitumen; waxes such as for example, beeswax, paraffinwax, and chlorinated mineral waxes; and solid fertilisers, for examplesuperphosphates.

Examples of suitable fluid carriers are water, alcohols, such as forexample, isopropanol, glycols; ketones such as for example, acetone,methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; ethers;aromatic hydrocarbons such as for example, benzene, toluene and xylene;petroleum fractions such as for example, kerosine, light mineral oils;chlorinated hydrocarbons, such as for example, carbon tetrachloride,perchloroethylene, trichloroethane, including liquefied normallyvaporous gaseous compounds. Mixtures of different liquids are oftensuitable.

The surface-active agent may be an emulsifying agent or a dispersingagent or a wetting agent; it may be nonionic or ionic. Any of thesurface-active agents usually applied in formulating herbicides,fungicides, or insecticides may be used. Examples of suitablesurface-active agents are the sodium or calcium salts of polyacrylicacids and lignin sulphonic acids; the condensation products of fattyacids or aliphatic amines or amides containing at least 12 carbon atomsin the molecule with ethylene oxide and/or propylene oxide; fatty acidesters of glycerol, sorbitan, sucrose or pentaerythritol; condensates ofthese with ethylene oxide and/or propylene oxide; condensation productsof fatty alcohols or allyl phenols for example p-octylphenol orp-octylcresol, with ethylene oxide and/or propylene oxide; sulphates orsulphonates of these condensation products; alkali or akaline earthmetal salts, preferably sodium salts, of sulphuric or sulphonic acidesters containing at least 10 carbon atoms in the molecule, for example,sodium lauryl sulphate, sodium secondary alkyl sulphates, sodium saltsof sulphonated castor oil, and sodium alkylaryl sulphonates such assodium didecylbenzene sulphonate; and polymers of ethylene oxide andcopolymers of ethylene oxide and propylene oxide.

The compositions of the invention may be formulated as wettable powders,dusts, granules, solutions, emulsifiable concentrates, emulsions,suspension concentrates and aerosols and will generally contain 0.5 to95% w, preferably 0.5 to 75% w, of toxicant. Wettable powders areusually compounded to contain 25, 50 or 755 % of toxicant and usuallycontain, in addition to solid carrier, 3-10% w of a dispersing agentand, where necessary, 0-10% w of stabliser(s) and/or other additivessuch as penetrants or stickers. Dusts are usually formulated as a dustconcentrate having a similar composition to that of a wettable powderbut without a dispersant, and are diluted in the field with furthersolid carrier to give a composition usually containing 1/2-10% w oftoxicant. Granules are usually prepared to have a size between 10 and100 BS mesh (1.676-0.152 mm), and may be manufactured by agglomerationor impregnation techniques. Generally, granules will contain 1/2-25% wtoxicant and 0-10% w of additives such as stabilisers, slow releasemodifiers and binding agents. Emulsifiable concentrates usually contain,in addition to the solvent and, when necessary, co-solvent, 10-50% w/vtoxicant, 2-20% w/v emulsifiers and 0-20% w/v of appropriate additivessuch as stabilisers, penetrants and corrosion inhibitors. Suspensionconcentrates are compounded so as to obtain a stable, non-sedimenting,flowable product and usually contain 10-75% w toxicant, 0.5-15% w ofdispersing agents, 0.1-10% w of suspending agents such as protectivecolloids and thixotropic agents, 0-10% w of appropriate additives suchas defoamers, corrosion inhibitors, stabilisers, penetrants andstickers, and as carrier, water or an organic liquid in which thetoxicant is substantially insoluble; certain organic salts may bedissolved in the carrier to assist in preventing sedimentation or asantifreeze agents for water.

Aqueous dispersions and emulsions, for example, compositions obtained bydiluting a wettable powder or a concentrate according to the inventionwith water, also lie within the scope of the present invention. The saidemulsions may be of the water-in-soil or of the oil-in-water type, andmay have a thick `mayonnaise`-like consistency.

The compositions of the invention may also contain other ingredients,for example, other compounds possessing pesticidal, for exampleinsecticidal, acaricidal, herbicidal or fungicidal properties.

The invention is further illustrated in the following Examples:

EXAMPLE I 2-isopropyl 4-methylpent-4 enoic acid, alpha-cyano-3phenoxybenzyl ester

(a) Preparation of 2-isopropyl-4-methylpent-4-enoic acid

Diethylmalonate (80.0g) in ethyl alcohol (50ml) was added to a solutionof sodium ethoxide (prepared from sodium metal (13.0g) and absolutealcohol (400ml)) over 15 minutes whilst gently refluxing the mixture.After stirring under reflux for 1 hour a solution of 2-bromopropane(74.5g) in alcohol (50ml) was added over 1 hour and the mixture stirredunder reflux overnight. The reaction mixture was cooled in ice andinorganic material removed by filtration and the filtrate concentrated.Water was added to the concentrate which was extracted with ether, theethereal extracts washed with 2N sodium hydroxide solution (X2) anddried over magnesium sulphate. Removal of solvent gave an almostcolourless liquid which was further purified by distillation to givediethyl isopropylmalonate b.p. 62°-65° C/0.7 mm Hg.

A solution of diethyl isopropylmalonate (8.1g) in 25 ml of a 25%solution of HMPT (hexamethylphosphorus triamide) in toluene was addeddropwise over 15 minutes to a suspension of sodium hydride (50mM) in 25%HMPT/toluene (50ml) at room temperature. The mixture was then stirred at60° C for 1/2 hour, cooled to 25° C and methallyl chloride (4.0g) in 25%HMPT/toluene was added over 10 minutes. The mixture was stirred at80°-85° C overnight, cooled to room temperature and poured onto amixture of ice/hydrochloric acid. The product was extracted with ether,the ethereal extracts washed with water, followed by 2N sodium hydroxideand then water, and dried over magnesium sulphate. Removal of solventgave diethyl isopropyl-2-methylprop-2-enylmalonate as a pale yellowliquid. R.I. n_(D) ²¹ 1.4467.

A mixture of diethyl isopropyl-2-methylprop-2-enylmalonate (8.7g),potassium hydroxide (20g), water (20ml) and methylated spirits (10ml)was stirred under reflux overnight. The mixture was diluted with water(200ml) and washed with ether (X3). The aqueous portion was acidifiedwith conc. hydrochloric acid and the acid product extracted with ether(X3), washed with water and dried over magnesium sulphate. Removal ofsolvent gave the disubstituted malonic acid (5.3g) which was thendecarboxylated at 200° C for 11/2 hours under nitrogen. the crudeproduct was dissolved in ether, washed with water and the etherealextract treated with 2N sodium hydroxide (X2) and washed with ether. Theaqueous phase was acidified with conc. hydrochloric acid and the productextracted with ether (X2) washed with water and dried over magnesiumsulphate. Removal of solvent gave the required2-isopropyl-4-methylpent-4-enoic acid. R.I. n_(D) ²¹ = 1.4459.

Analysis: Calculated for C₉ H₁₆ O₂ : C 69.2; H 10.3. Found: C 69.4; H10.7.

(b) Esterification of 2-isopropyl-4-methylpent-4-enoic acid

A mixture of 2-isopropyl-4-methylpent-4-enoic acid (1.0g),alphacyano-3-phenoxybenzyl bromide (1.9g) and potassium carbonate (1.0g)in anhydrous acetone (40ml) was stirred at room temperature for 4 hours.Water was added to the reaction mixture and the product extracted withether, the ethereal extracts washed with water (X2) and dried overmagnesium sulphate. Evaporation of the solvent gave a crude productwhich was purified by chromatography on silica gel using 3% acetone in60°-80° C petroleum ether as eluent to give the desired ester. R.I.n_(D) ²⁰ 1.5343.

Analysis: Calculated for C₂₃ H₂₅ NO₃ : C 76.1; H 6.9; N 3.9%. Found: C76.0; H 7.0; N 3.6%.

EXAMPLE 2 Preparation of 2-isopropylpentanoic acid,alpha-cyano-3-phenoxy benzyl ester

(a) Preparation of 2-isopropylpentanoic acid

Diethylmalonate (80.0g) in ethyl alcohol (50ml) was added to a solutionof sodium ethoxide (prepared from sodium metal (13.0g) and absolutealcohol (400ml)) over 15 minutes whilst gently refluxing the mixture.After stirring under reflux for 1 hour a solution of 2-bromopropane(74.5g) in alcohol (50ml) was added over 1 hour and the mixture stirredunder reflux overnight. The reaction mixture was cooled in ice andinorganic material removed by filtration and the filtrate concentrated.Water was added to the concentrate which was extracted with ether, theethereal extracts washed with 2N sodium hydroxide solution (X2) anddried over magnesium sulphate. Removal of solvent gave an almostcolourless liquid which was further purified by distillation to givediethyl isopropylmalonate b.p. 62°-65° C/0.7 mm Hg.

A solution of diethylisopropylmalonate (10.1g) in 15 ml of a 25%solution of HMPT (hexamethylphosphorus triamide) in toluene was addeddropwise over 15 minutes to a suspension of sodium hydride (70mM) in 25%HMPT/toluene (15ml) at 50°-70° C. N-propyl iodide (17.0g) was then addedover 30 minutes at 70°-100° C and the mixture stirred at 120°-130° C for11/2 hours. After cooling, methylated spirits (10ml) was added and themixture poured onto a mixture of ice/hydrochloric acid. The product wasextracted with ether, the ethereal extracts washed with sodiumbicarbonate (X2), then water and dried over anhydrous magnesiumsulphate. Removal of the solvent gave diethyl2-isopropyl-2-propylmalonate as a yellow liquid b.p. 92°-94°/1 mm Hg.87% yield.

Analysis: Calculated for C₁₃ H₂₄ O₄ : C 63.9; H 9.8% Found: C 63.1; H10.1%.

A mixture of diethyl 2-isopropyl-2-propylmalonate (10.0g), potassiumhydroxide (20g), water (20ml) and methylated spirits (10ml) was stirredunder reflux overnight. After dilution with water (200ml) the mixturewas washed with ether (X2). The aqueous portion was acidified with conc.hydrochloric acid and the acid product extracted with ether (X3), washedwith water and dried over anhydrous magnesium sulphate. Removal ofsolvent gave the disubstituted malonic acid which was thendecarboxylated by stirring overnight in gently reluxing xylene (60ml).The reaction product was cooled in an ice bath, diluted with ether,washed with water (X2) and the ethereal extract treated with 2M sodiumhydroxide (X2). The basic aqueous phase was acidified with conc.hydrochloric acid and the product extracted with ether (X2), washed withwater and dried over anhydrous magnesium sulphate. Removal of solventgave the required 2-isopropylpentanoic acid R.I. n_(D) ²¹ 1.4263. Yield85%.

Analysis: Calculated for C₈ H₁₆ O₂ : C 66.7; H 11.1%. Found: C 66.4; H11.0%.

(b) Esterification of 2-isopropylpentanoic acid

A mixture of 2-isopropylpentanoic acid (0.8g),alpha-cyano-3-phenoxybenzyl bromide (1.45g) and potassium carbonate(0.8g) in anhydrous acetone (30ml) was stirred at room temperature for 2hours. Water was added to the reaction mixture and the product extractedwith ether, the ethereal extracts washed with sodium bicarbonate (X3)and dried over anhydrous magnesium sulphate. Evaporation of the solventgave a crude product which was purified by chromatography on silica gelusing 3% acetone in 60°-80° C petroleum ether as eluent to give thedesired ester. R.I. n_(D) ²¹ 1.5237.

Analysis: Calculated for C₂₂ H₂₅ NO₃ : C 75.2; H 7.1; N 4.0. Found: C75.4; H 7.4; N 3.6.

EXAMPLE 3 Preparation of 2-allyl isovaleric acid, alphathioamido-3-phenoxy benzyl ester

2-allyl isovaleric acid, alpha-cyano-3-phenoxy benzyl ester (prepared ina manner analogous to that of Example 3; 3.5g), dimethyl formamide(30ml), and triethanolamine (4ml) were stirred together at roomtemperature, the apparatus purged with dry nitrogen gas for 15 minutes,and a slow stream of hydrogen sulphide gas then bubbled through themixture for 3 hours at room temperature. Nitrogen gas was then passedthrough the mixture to remove excess hydrogen sulphide, leaving a clear,light green solution. This product was poured into water, extractedtwice with diethyl ether, washed with water (X6) and dried overanhydrous magnesium sulphate. Removal of the ether solvent gave a crudeproduct as a yellow oil, which was purified by chromatography on silicagel using methylene dichloride as eluant to yield the desired product.R.I. n_(D) ²³ = 1.5843.

Analysis: Calculated for C₂₂ H₂₅ NSO₃ : C 69.0; H 6.5; N 3.6; S 8.3%.Found: C 68.5; H 6.2; N 3.5; S 8.2%.

EXAMPLE 4-30

Following procedures similar to those described in Example 1-3, furthercompounds according to the invention were prepared. The physicalcharacteristics and analyses are given in Table 1 in which the compoundsare identified by reference to the substituents in formula I.

EXAMPLE 31 Pesticidal activity

The insecticidal, acaricidal and tickicidal activity of the compoundsaccording to the present invention was tested as follows:

I. A 1.0% by weight solution in acetone of the compound to be tested wasprepared, and taken up in a micrometer syringe. Two to 3-day old adultfemale house flies (Musca domestica) was anaesthetized with carbondioxide, and 1 μl drop of the test solution was brushed off on theventral abdomen of each, 20 flies being treated. The treated flies wereheld for 24 hours in glass jars, each containing a little granulatedsugar as food for the flies, and the percentage of dead and moribundindividuals was then recorded.

                                      TABLE I                                     __________________________________________________________________________    Ex.                         R.I.                                              No. R         X   Y         or m.p.                                                                              Analysis                                   __________________________________________________________________________    4   isopropyl --CN                                                                              3-phenoxyphenyl                                                                         n.sub.D.sup.23 1.5320                                                                Calculated for C.sub.22 H.sub.25                                              NO.sub.3        C 75.2 ; 7.1 ; N 4.0%                                         Found          C 74.1 ; H 6.8 ; N                                                            3.7%                        5   isopropyl H   "         n.sub.D.sup.23 1.5260                                                                Calculated for C.sub.21 H.sub.26                                              O.sub.3        C 77.2 ; H 8.0%                                                Found          C 77.7 ; H 8.2%             6   p-chlorobenzyl                                                                          --CN                                                                              "         n.sub.D.sup.20 1.5360                                                                Calculated for C.sub.26 H.sub.24                                              NO.sub.3 Cl    C 72.0 ; H 5.5 ; N                                                            3.2%                                                           Found          C 70.8 ; H 5.6 ; N                                                            2.9%                        7   m-chlorobenzyl                                                                          --CN                                                                              "         n.sub.D.sup.20 1.5620                                                                Calculated for C.sub.26 H.sub.24                                              NO.sub.3 Cl    C 72.0 ; H 5.5 ; N                                                            3.2%                                                           Found          C 71.9 ; H 5.3 ; N                                                            3.0%                        8   2,3-dimethylbenzyl                                                                      --CN                                                                              "         n.sub.D.sup.20 1.5582                                                                Calculated for C.sub.28 H.sub.29                                              NO.sub.3       C 78.6 ; H 6.8 ; N                                                            3.3%                                                           Found          C 78.6; H 6.8 ; N 3.1%      9   "         H   "         n.sub.D.sup.20 1.5601                                                                Calculated for C.sub.27 H.sub.30                                              O.sub.3        C 80.6; H 7.5%                                                 Found          C 80.9 ; H 7.6%             10  allyl     CN  "         n.sub.D.sup.20 1.5345                                                                Calculated for C.sub.22 H.sub.23                                              NO.sub.3       C 75.6 ; H 6.6 ; N                                                            4.0%                                                           Found          C 76.0 ; H 6.9 ; N                                                            3.9%                        11  3-methyl allyl                                                                          CN  "         n.sub.D.sup.21 1.5358                                                                Calculated for C.sub.23 H.sub.25                                              NO.sub.3       C 76.1 ; H 6.9 ; N                                                            3.9%                                                           Found          C 76.2 ; H 7.0 ; N                                                            3.7%                        12  3,3-dimethyl allyl                                                                      CN  "         n.sub.D.sup.19 1.5331                                                                Calculated for C.sub.24 H.sub.27                                              NO.sub.3       C 76.4 ; H 7.2 ; N                                                            3.7%                                                           Found          C 76.7 ; N 7.2 ; N                                                            3.5%                        13  n-butyl   --CN                                                                              "         n.sub.D.sup.21 1.5232                                                                Calculated for C.sub.23 H.sub.27                                              NO.sub.3       C 75.6 ; H 7.4 ; N                                                            3.8%                                                           Found          C 75.3 ; H 7.3 ; N                                                            3.7%                        14  ethyl     --CN                                                                              "         n.sub.D.sup.21 1.5302                                                                Calculated for C.sub.21 H.sub.23                                              NO.sub.3       C 74.7 ; H 6.8 ; N                                                            4.15%                                                          Found          C 75.11 ; H 6.9 ; N                                                           3.9%                        15  n-hexyl   --CN                                                                              "         n.sub.D.sup.21 1.5189                                                                Calculated for C.sub.25 H.sub.31                                              NO.sub.3       C 76.3 ; H 7.9 ; N                                                            3.55%                                                          Found          C 76.0 ; H 8.1 ; N                                                            3.4%                        16  n-propyl  H   "         n.sub.D.sup.22 1.5285                                                                Calculated for C.sub.21 H.sub.26                                              O.sub.3        C 77.3 ; H 8.0%                                                Found          C 77.4 ; H 8.0%             17  n-butyl   --C.tbd.CH                                                                        "         n.sub.D.sup.18 1.5312                                                                Calculated for C.sub.24 H.sub.30                                              O.sub.3        C 79.1 ; H 7.7%                                                Found          C 79.0 ; H 7.9%             18  n-dodecyl --CN                                                                              3-phenoxyphenyl                                                                         n.sub.D.sup.20 1.5090                                                                Calculated for C.sub.31 H.sub.43                                              NO.sub.3       C 78.0 ; H 9.0 ; N                                                            2.9%                                                           Found          C 78.3; H 9.5 ; N 2.7%      19  n-octyl   --CN                                                                              "         n.sub.D.sup.22 1.5154                                                                Calculated for C.sub.27 H.sub.35                                              NO.sub.3       C 77.0 ; H 8.3 ; N                                                            3.3%                                                           Found          C 77.3 ; H 8.5 ; N                                                            3.0%                        20  methyl    --CN                                                                              "         n.sub.D.sup.22 1.5345                                                                Calculated for C.sub.20 H.sub.21                                              NO.sub.3       C 74.3 ; H 6.5 ; N 4.3                                         Found          C 74.1 ; H 6.7 ; N                                                            4.0%                        21  3,3-dimethyl allyl                                                                      --C.tbd.CH                                                                        "         n.sub.D.sup.22 1.5340                                                                Calculated for C.sub.25 H.sub.28                                              O.sub.3        C 79.8 ; H 7.5%                                                Found          C 79.8 ; H 7.5%             22  isoamyl   CN  3-phenoxyphenyl                                                                         n.sub.D.sup.22 1.5194                                                                Calculated for C.sub.24 H.sub.29                                              NO.sub.3       C 76.0 ; H 7.6 ; N                                                            3.7%                                                           Found          C 75.6 ; H 7.6; N 3.4%      23  isobutyl  CN  "         n.sub.D.sup.24 1.5220                                                                Calculated for C.sub.23 H.sub.27                                              NO.sub.3       C 75.6 ; H 7.4 ; N                                                            3.8%                                                           Found          C 75.6 ; H 7.5 ; N                                                            3.6%                        24  pentenyl-1                                                                              CN  "         n.sub.D.sup.22 1.5298                                                                Calculated for C.sub.24 H.sub.27                                              NO.sub.3       C 76.4 ; H 7.2 ; N                                                            3.7%                                                           Found          C 76.1 ; H 7.3 ; N                                                            3.3%                        25  3,3-dimethyl allyl                                                                      H   phthalimido                                                                             n.sub.D.sup.22 1.5026                                                                Calculated for C.sub.19 H.sub.27                                              NO.sub.4       C 68.4 ; H 8.1 ; N                                                            4.2%                                                           Found          C 68.2 ; H 8.1 ; N                                                            3.9%                        26  allyl     H   "         n.sub.D.sup.23 1.5316                                                                Calculated for C.sub.17 H.sub.19                                              NO.sub.4       C 67.8 ; H 6.3 ; N                                                            4.7%                                                           Found          C 68.0 ; H 6.3 ; N                                                            4.8%                        27  n-hexyl   H   "         n.sub.D.sup.18 1.5091                                                                Calculated for C.sub.20 H.sub.31                                              NO.sub.4        C 68.7 ; H 8.9 ; N                                                           4.0%                                                           Found          C 68.3 ; H 9.2 ; N                                                            3.7%                        28  C.sub.2 H.sub.5                                                                         H   "         m. pt. 48-9° C                                                                Calculated for C.sub.16 H.sub.19                                              NO.sub.4       C 66.5 ; H 6.6 ; N                                                            4.8%                                                           Found          C 66.2 ; H 6.6 ; N                                                            4.8%                        29  CH.sub.3 OCH.sub.2                                                                      CN  "         n.sub.D.sup.18 1.5351                                                                Calculated for C.sub.21 H.sub.23                                              NO.sub.4       C 71.4 ; H 6.5 ; N                                                            4.0%                                                           Found          C 71.8 ; H 6.6 ; N                                                            3.8%                        30  (CH.sub.3).sub.3 C--CH.sub.2 --CH.sub.2                                                 CN  3-phenoxyphenyl                                                                         n.sub.D.sup.21 1.5179                                                                Calculated for C.sub.25 H.sub.31                                              NO.sub.3       C 76.4 ; H 7.9 ; N                                                            3.5%                                                           Found          C 76.1 ; H 8.1 ; N          __________________________________________________________________________                                                      3.3%                    

II. The compounds were formulated as solutions or suspensions in watercontaining 20% by weight of acetone and 0.05% by weight of Triton X 100as wetting agent. The formulations contained 0.7% by weight of thecompound to be tested. Turnip and broad bean plants, trimmed to one leafeach, were sprayed on the under-surface of the leaf with the aboveformulation. Spraying with a spraying machine delivering 450 liters perhectare, the plants passing under the spray on a moving belt. Ten adult1-2 week-old mustard beetles (Phaedon cochleariae) were placed on thespraying leaf of each turnip plant and ten apterous (6-day-old) vetchaphids (Megoura viciae) were placed on the sprayed leaf of each broadbean plant. The plants were then enclosed in glass cylinders fitted atone end with a muslin cap. Mortality counts were made after 24 hours.

III. In tests against glass house spider mites (Tetranychus urticae),leaf discs cut from French bean plants were sprayed in the mannerdescribed under II. 1 hour after spraying, the discs were inoculatedwith 10 adult mites. Mortality counts were made 24 hours afterinoculation.

IV. The compounds were formulated as solutions or fine suspensions inwater containing 20% by weight of acetone and 0.05% by weight of TritonD 100 as wetting agent. The formulations contained 0.6% by weight of thecompound to be tested. Pairs of leaves are removed from broad beanplants and placed on filter paper inside plastic petri dishes.Immediately prior to testing 10 larvae of the Egyptian cotton leafworm(Spodoptera littoralis) are transferred onto the leaves and allowed tosettle down. Larvae and leaves are sprayed together using a sprayingmachine delivering 340 liters/hectare. operated under the conveyor beltprinciple. After spraying the larvae are covered with a petri dish lid.After 24 hours, the percentage of dead and moribund larvae was recorded.

V. The compounds were formulated as solutions or fine suspensions inacetone containing 10% by weight of polyethylene glycol having anaverage molecular weight of 400. The formulations contained 0.1% byweight of the compound to be tested. 1 ml of the above-mentionedsolution is applied evenly to a filter paper situated inside a petridish. After the paper is sufficiently dry it is folded in half andpartly crimped along the outer edge to form a packet. About 80-100larval ticks (Boophilus microplus) are transformed into the packet whichis then sealed completely. The packets are placed inside an incubator,maintained at 27° C and 80% relative humidity, before assessingmortality 24 hours later.

The results of these tests are shown in Table II in which the testspecies are identified by the initials noted above, and A denotescomplete kill, B some kill and C no kill of the test species.

                  TABLE II                                                        ______________________________________                                        Compound of                                                                             Pesticidal Activity                                                 Example   M.d.    P.c.    S.l.  M.v.  T.u.  B.m.                              ______________________________________                                        1         A       B       A     A     B     A                                 2         A       A       A     A     B     A                                 3         C       C       C     A     B     B                                 4         A       B       B     A     B     A                                 6         A       B       B     A     C     B                                 8         C       C       C     B     B     A                                 9         C       C       A     C     B     C                                 10        A       A       A     A     A     A                                 11        A       B       C     A     B     A                                 13        A       B       C     A     A     A                                 14        A       A       A     A     B     A                                 15        A       B       A     A     B     A                                 16        C       B       C     A     B     A                                 17        A       B       A     A     B     A                                 19        C       B       C     A     B     A                                 21        B       A       C     A     C     B                                 22        A       C       A     A     A     A                                 23        A       C       A     --    A     --                                24        A       B       A     B     C     A                                 27        C       B       C     A     B     B                                 ______________________________________                                    

What we claim is:
 1. A compound of the formula ##STR5## wherein R is astraight-chain alkyl group of 1 to 16 carbon atoms and X is a hydrogenatom or an ethynyl group.
 2. A compound according to claim 1 wherein Ris n-propyl and X is ethynyl.
 3. A compound as claimed in claim 1wherein R is n-propyl and X is hydrogen.